Resilient lamp mounting



`Ian. 23, 1962 Filed Feb. 27, 1961 w. A. wENMN 3,018,364

RESILIENT LAMP MOUNTING I5 Sheets-Sheeil 1 Jan. 23, 1962 w. A. wENMAN 3,018,364

RESILIENT LAMP MOUNTING Filed eb. 27, 1961 3 Sheets-Sheet 2 nowNANT 'f Jan. 23, 1962 W. A. WENMAN RESILIENT LAMP MOUNTING Filed Feb. 27, 1961 3 Sheets-Sheet 3 United States Patent O 3,018,364 RESILIENT LAMP MOUNTING William A. Weuman, Milwaukee, Wis., assignor to Phoenix Products Company, Inc., Milwaukee, Wis., a corporation of Wisconsin Filed Feb. 27, 1961, Ser. No. 92,093 13 Claims. (Cl. 240-90) This invention relates to lighting fixtures generally, and like that of the pending application Serial No. 858,810, filed December l0, 1959, and now forfeited, of which this is a continuation-in-part, has as its purpose to provide an improved resilient mounting for electric lamps, and especially those of the sealed-beam variety, with a View towards improving the life of such lamps when used in lighting fixtures mounted on rugged earth working machinery and tractors, and in other environments in which the fixtures are subjected to severe vibration or shock.

Although lamp manufacturers have been able to design and produce electric lamps capable of withstanding considerable vibration without filament failure, even the best of these lamps have a relatively short life unless they are mounted in such a way that the transmission of vibration and shock imparted to the xture in which the lamps are mounted is adequately cushioned and held to a minimum.

The need for such resilient lamp mountings has been recognized for some time, and various means have been devised in the past in an effort to satisfy this need. The patent to Falge No. 2,800,578, is an example of these past attempts.

For one reason or another, however, all lamp mountings heretofore available have had serious limitations. Usually they were too complicated. Often they were so constructed that removal and replacement of the lamp was difcult, and some of them did not support the lamp by its peripheral rim, which is by far the most desirable way of supporting a sealed-beam lamp for the type of service contemplated.

By contrast, the present invention provides an extremely simple and greatly improved resilient mounting for sealed-beam electric lamps, which is characterized by an exceptionally resilient weather-tight connection between the lamp receptacle and the lamp casing.

'I'he invention also features a lamp receptacle of greatly simplified construction, so designed as to make securement of the lamp to the receptacle by means of the marginal or peripheral rim on the lamp an extremely simple matter. In this connection, it is also a feature of this invention to provide means by which the lamp may be positively held in any one of a number of predetermined positions of rotation within the casing so that it may be positioned with its filament most favorably oriented with respect to the direction of dominant vibration.

With the above and other objects in view which will appear as the description proceeds, this invention resides in the novel construction, combination and arrangement of parts substantially as hereinafter described and more particularly defined by the appended claims, it being understood that such changes in the precise embodiment of the hereindisclosed invention may be made as come within the scope of the claims.

The accompanying drawings illustrate two complete examples of the physical embodiment of the invention con- ICC structed according to the best mode so far devised for the practical application of the principles thereof, and in which:

FIGURE '1 is a perspective view of a light fixture ernbodying this invention;

FIGURE 2 is a longitudinal section view through the fixture, with parts broken away and in section;

FIGURE 3 is a fragmentary section View on the same plane as that of FIGURE 2, but at an enlarged scale;

FIGURE 4 is a front view of the fixture with parts broken away to better illustrate structural details;

, FIGURES 5 and 6 are diagrammatic views to illustrate the manner in which the lamp may be secured in different positions of rotation with its lament most favorably oriented with respect to the direction of dominant vibration;

FIGURE 7 is a longitudinal section View through an explosion proof light fixture embodying this invention in slightly modified form; and

. FIGURE S is a fragmentary section view on the same plane as that of FIGURE 7, but at enlarged scale to better illustrate the relationship of the parts comprising the rcsilient lamp mounting in this modified embodiment of the invention.

Referring now particularly to the accompanying drawings, and especially to FIGURES 1 through 6, the numeral 7 designates the casing of a light fixture of one type with which this invention is concerned. In it is mounted an electric lamp 8 of the sealed-beam variety, by means of a resilient shock absorbing mounting, designated generally by the numeral 9.

The casing 7 consists of a metal shell having a cylindrical side wall 10, and an end wall 11 closing the rear thereof. The front of the casing is open, and preferably the upper portion of the front end projects beyond the lower part thereof to provide a hood 12.

A yoke 13 embraces the casing and is pivotally connected thereto at diametrically opposite points, as at 14. The closed end or bight of this yoke is fixed to a spindle or stud 15 which is rotatably mounted upon a base 16 by which the entire fixture may be mounted upon the apparatus with which the light is to be used. Preferably the mounting of the spindle upon the base incorporates some form of cushioning, but this forms no part of the present invention.

An electric supply cord 17 enters the casing, preferably vat its bottom, as shown, and inside the casing this supply cord is connected by means of flexible conductors 18 with a socket 19 into which the terminal prongs (not shown) of the lamp 8 are inserted, to thus connect the filament 20 of the lamp with the current source. Y Attention is directed to the fact that the socket 19 has no connection with the casing, except that formed by the fiexible conductors 18. Consequently the socket 19 is supported from the lamp.

Although the lamp 8 is of standard design and manufacture, it is important to observe that its filament 20 and the mounting thereof has been designed to accommodate vibration in one definite direction, far better than it can in other directions. Thus, as best seen in FIGURE 4, the filament 20 occupies a plane which contains the axis of the lamp, and is supported at its ends by two'post-like elements 21, which project forwardly 3. from the base of the lamp to which they are anchored. Accordingly, the filament may vibrate more or less freely in a direction normal to the plane containing the lament without serious consequences, but since its freedom to vibrate in other directions is constrained, the lamp should be mounted with the plane containing the ilament normal to the direction of the dominant vibration to which the xture is subjected.

As will be hereinafter more fully described, the resilient mounting 9 incorporates means to hold the lampI in a position of rotation in which its filament is most favorably oriented with respect to the direction of dominant vibration.

As is customary in lamps of the sealed-beam type with which this invention is concerned, the lamp `8 comprises a glass envelope, the front ofwhich is defined by a lensV 23, and the rear by abowl-'shaped reiiectorf'24. At the junction of thesevtwo parts, the lamphas a marginal orY peripheral rim with well dened front and rearV edges, and at a point lying in a plane normal -to that containing the filament there is a locating lug 26 formed integrallyn with the rim 25 and projecting rearwardly therefrom.

The lamp is readily removably mounted in its resilient mounting 9 and, to this end, the mounting 9 comprises a lamp receptacle indicated generally by the numeral 27' and consisting of a metal locating ring 28 and a metall clamping ring 29 which cooperate to grip the lamp by its. rim 25. The locating ring 28 hasa truncated conical medial or intermediate portion 30 of a size such that its. smallest diameter is less than that ofthe rim 25, while: its largest diameter is greater than that ofthe rim 25- Hence, upon insertion of the lamp into the locating ring, its rim abuts or seats upon the conical surface of the medial portion 30.

At its small diameter end, the locating ring has a rear flange 31, and at its large diameter end it has a front ange 32. These flanges are flat and parallel with one another; and preferably the outer edge of the larger front flange is turned back to providea smooth surfaced locating and stiffening rim 33.

At three equisp'aced points around its circumference, the flange 32 has internally threaded rea-rwardlyvprojecting bosses 34 fixed thereto. These bosses have clamping screws 35'preferably thumb screws-threaded into them, andthe headed ends of the screws are operativelyr engageable with the clamping ring without requiring their removal' from the bosses 34. When so engaged and tightened, the screws draw the clamping ring toward the locating ring to thereby grip the lamp rim 25 therebetween: Disengagement of the clamping ring from the headed ends of the screws allows the clamping ring to be removed for removal of the lamp; and for the sake of conveniencein changing lamps, a tether 36 connects the clamping ring with the casing.

The detachable connection between the clamping ring and the headedends of the screws is provided by key hole shaped apertures 37 in the clamping ring, the large ends of which permit the heads of the screws to be passed therethrough. Obviously, upon proper placement of the clamping ring on the locating ring and rotation of the former to dispose the screws in the narrow ends of the keyhole shaped apertures, the parts are in position to secure the lamp in place by tightening the thumb screws. Properplacement of the clamping ring upon the locating ring is facilitated by the guidance obtained from the engagement of a rearwardly projecting peripheral ange 38 on the clamping ring with the rim 33 onthe locating ring, and by the provision of diametrically opposite forwardly projecting pins 39 on the clamping ring which provide handles for the clamping ring.

As, will be appreciated, tightening of the clamping screws 35 clamps'therim 25 of the lamp Ybetween the Y'frustoc'onical ,medial portion of the locatingrring and the inner' edge portion of the clamping ring, and to cushion this latter engagement, the inner edge of the clamping ring is sheathed in rubber 40.

Attention is directed to the fact that the locating ring has a plurality of holes 41 in its truncated conical portion, so positioned that the locating lug 26 on the lamp may enter any one of them when the lamp is seated in its receptacle. It is these holes 41, in conjunction with the lug 26 which enables the lamp to be properly oriented with respect to the direction of dominant vibration, as diagrammatically illustrated in FIGURES 5 and 6.

Attention is also directed to the fact that the telescoping connection between the ange 38 on the clamping ring and the rim 33 of the locating ring affords a relatively tight closure, and that the rubber sheath bearing against the frontof the lamp rim 25, effects a weathertight seal at this point. Thus, by having the resilient mounting 9 weather-proof, and the closed rear end of the casing imperforate, Vthe current carrying portion of the lamp and its socket are fully and completely protected against the weather.

The resilient mounting` 9 comprises a rubber ring or annular diaphragm 42 having dat inner and outer edge portions 43 and 44,7respectively, connected by an intermediate portion `45 which is U-shaped in cross section, and hence radially yieldable. Preferably all portions of the ring or diaphragm have the same wall thickness. The inner and outer edge portions of the resilient ring or diaphragm are reinforced by being confined between metal rings 47, which are tied together and clamped to the opposite sides of the rubber ring by rivets 48.

The rubber mounting ring is clamped to the rear of the flange 31 on the locating ring of the lamp receptacle by screws 49 which pass through the rubber ring and the adjacent rings 47, to be threaded into the ilange 31, as shown. Preferably, the inner edge of the resilient ring has a forwardly projecting marginal bead 50 which bears tightly against the rounded inner edge of the flange 31, or more specifically its junction with the truncated conical portion 30, to assure a weather-tight seal at this point. The outer edge portion 44 of the resilient ring is removably clamped to the front of a flange 51 by screws 52 which pass through the ring and are threaded into the ange 51. This liange is fixed to the inside of the casing in any suitable manner and lies in a plane normal to the lamp axis.

lMounting the resilient ring or annulus and connecting it to. thelamp receptacle in the manner described enables ready assembly of the parts for, as will be appreciated, it is a simple matter to first attach the rubber annulus to the back of the lamp receptacle, insert the resulting subassembly into the lamp casing, and then Secure the annulus to the flange 51 by the screws 52, the heads of which face forwardly.

As will also be readily appreciated, by virtue of the specific cross ysectional shape of the rubber annulus, its inner and outer edge portions are relatively free to move radially with respect to one another, to thereby absorb vibration and shock imparted to the lamp casing, so that the lamp which is secured in the lamp receptacle is substantially protected against the transmission of vibratory shock thereto.

While it would appear that it is desirable to have the U-shaped cross sectional shape of the intermediate portion 45 of the cushioning ring continue unbrokenly `all around its circumference, it has been found advantageous to connect the inner and outer portions of the ring by integral radial ribs 53 at a few widely spaced locations-preferably at three equispaced points.

FIGURES 7 and 8 illustrate a slightly modified embodiment of the invention incorporated in an explosionsealed port, and its leads connect with the socket 19 to supply current to the filament of the lamp 8 as in the other already described form of the invention.

Except for the specific construction of the casing and the fact that the connection of the rubber cushioning ring with the casing Wall and with the' lamp receptacle is reversed from what it is in the fixture shown in FIGURES 1 to 4, inclusive, the structure shown in FIGURES 7 and 8 is the same as that already described. Thus, it is the inner edge portion 43 of the cushioning ring which is secured to the casing, and the outer edge portion 44 which is secured to the lamp receptacle 27 in this modilied embodiment of the invention. By this reversal, compactness without undue crowding and a practical easily assembled structure is attained.

Securement of the inner edge portion 43 of the rubber annulus to the casing is effected by screws 64 threaded into a forwardly extending neck 65 cast integrally with the casing, the screws being readily accessible through the front of the casing before the lamp receptacle is secured to the cushioning ring and, of course, before the glass window 61 is in place.

To adapt the lamp receptacle 27 to this reversed mounting of the cushioning ring, its locating ring 28 is simply provided with a wider rim 33 and an outwardly directed flange 65 on the rear edge of this rim. Fastening screws 66 passed through aligned holes in the ange 65 and the outer edge portion 44 of the cushioning ring and threaded into tapped holes in a metal backup ring 67 fixed to the rear face of the outer edge portion 44 of the cushioning ring, removably secure the lamp receptacle to the ring.

AFrom the foregoing description taken in connection with the accompanying drawings, it should be readily apparent to those skilled in the art, that by virtue of the novel manner in which the lamp receptacle is resiliently mounted in the fixture, and the lamp secured in its most favorable orientation with respect to the direction of the dominant vibration imparted to the lamp fixture during use, this invention constitutes a substantial advance in the art.

It should also be evident that the removal and replacement of the lamp is materially facilitated by the present invention.

What is claimed as my invention is:

l. A resilient lamp mounting comprising: a casing having an open front end; means to mount the casing upon a support; an electric lamp having a filament contained within an envelope which has a lens circumscribed by a peripheral rim with well defined front and rear edges; a lamp receptacle to readily removably receive and mount the lamp, said receptacle comprising a locating ring member engaged by the rear edge of the peripheral rim on the lamp and having an outer portion encircling the rim, a clamping ring member engaging the front edge of the peripheral rim and overlying said outer portion of the locating ring member, and fastening means removably securing the clamping ring member in place and drawing said two members together to clamp the n'rn of the -lamp therebetween; and means resiliently mounting the lamp receptacle in the casing with the lamp facing the open end of the casing, said mounting means comprising an annulus of rubber-like material having an inner edge portion and an outer edge portion connected by an intermediate portion which is doubled back upon itself in cross section, so as to be radially yieldable; means securing one of said edge portions of the annulus to the lamp locating ring member; and means securing the other edge portion of the annulus to the casing.

2. The resilient lamp mounting of claim l, wherein the locating ring mem-ber has a forwardly facing frustoconical surface, the large diameter of which is greater than that of the rim on the lamp and the small diameter of which is smaller than the diameter of the lamp rim, said frustoconical inner surface providing a shoulder against which the rear edge of the lamp rim bears.

3. The resilient lamp mounting of claim 2, further characterized by the provision of means to locate the lamp in a predetermined position of rotation with respect to the casing, said means comprising a lug projecting from the rear edge of the rim on the lamp, and a hole in the frustoconical surface of the locating ring member in which said lug is received.

4. The resilient lamp mounting of claim 3, further characterized by the fact that the frustoconical surface of the locating ring member has a plurality of circumferentially spaced holes into any one of Iwhich said lug is insertable, to thereby enable the lamp to be secured against rotation in any one of a number of predetermined positions of rotation with respect to the casing.

5. The resilient lamp mounting of claim 1, wherein the cooperating ring members of the lamp receptacle have telescoping circular guide surfaces by which said members are held in coaxial alignment.

6. The resilient lamp mounting of claim 5, wherein the fastening means by which the cooperating ring members of the lamp receptacle are separably connected together comprises a plurality of headed screws having threaded engagement with the locating ring member and having their headed ends received in keyhole shaped apertures in the clamping ring member, the large ends of said keyhole shaped apertures permitting the heads of the screws to pass therethrough and allowing the clamping ring member to be placed in position on the locating ring member and rotated to bring the small ends of the keyhole shaped apertures under the heads of the screws; and handle means on the clamping ring member to facilitate assembling the same with the locating ring member.

7. The resilient lamp mounting of claim 1, wherein it is the inner edge portion of the annulus that is secured to the locating ring member of the lamp receptacle, and the outer edge portion of the annulus that is secured to the casing.

8. The resilient lamp mounting of claim 1, wherein it is the outer edge portion of the annulus that is secured to the locating ring member of the lamp receptacle, and the inner edge portion of the annulus that is secured to the casing.

9. The resilient lamp mounting of claim 7, wherein the inner and outer edge portions of the rubber-like annulus are at rings, and the intermediate portion thereof is U-shaped in cross section; wherein the locating ring member of the lamp receptacle has a flange with a flat rearwardly facing surface and the inner edge portion ofthe annulus lies at against said surface and is secured thereto; and wherein the casing has a flange with a. hat forwardly facing surface and the outer edge portion of the annulus lies at against said forwardly facing surface and is secured thereto.

l0. The resilient lamp mounting of claim 8, wherein the inner and outer edge portions of the rubber-like annulus are liat rings, and the intermediate portion thereof is U-shaped in cross section; wherein the locating ring member of the lamp receptacle has a ange with a at rearwardly facing surface and the outer edge portion of the annulus lies at against said surface and is secured thereto; and wherein the casing has a flange with a flat forwardly facing surface and the inner edge portion of the annulus lies at against said forwardly facing surface and is secured thereto.

11. The resilient lamp mounting of claim 9, wherein the securement of the annulus to said forwardly facing ilat surface of the casing comprises screws passing rearwardly through the outer edge portion of the annulus and threaded into said flange, the heads of said screws being accessible from the open front of the casing.

l2. The resilient lamp mounting of claim l0, wherein the securement of the inner and outer edge portions of the annulus to the at surfaces which they overlie comprises Screws passing rearwardly through the inner and outer edge portions of the annulus and threaded into the flanges, the heads of the screws being accessible from the front of the casing.

13. The resilient lamp mounting of claim 2, wherein the locating ring mem-ber of the lamp receptacle has an annular flange with forwardly and rearwardly facing surfaces, the latter joining with theV inner edge of the forwardly facing frustoconical surface; wherein the inner edge portion of the annulus las flat against and is secured to the rearwardly facing surface of said annular flange, and the outer edge portion of the annulus is secured Vto the casing; and further characterized by a forwardly proecting bead on the4 inner edge portion of the annulus 2,800,578 Page Ju1yf23, 1957 k2,824,214 {Bertsehe Feb. 18, 1958 2,826,682 Paige Mar. 11, 1958 2,894,693 Howarth July 14, 1959 2,910,576 Mees@ oct. 27, 1959 2,910,571 Bolmeyer Oct. 27, 1959v 

